Recent research has demonstrated the utility of spatio-temporal gait measures in augmenting the prospective evaluation of fall risk in the elderly. Although significant gains in fall risk evaluation in clinical and community-dwelling settings appears to be within reach, a significant hurdle is presented by the unavailability of a practical, low-cost commercial system to measure and assess both the spatial and temporal parameters of gait. Providing physicians and other care givers the tools to accurately assess fall risk will provide at least two benefits: (1) allow individuals at greater risk for falling to be identified and targeted for extra attention and interventions; and (2) reduce the fear of falling present in individuals who harbor an unwarranted degree of such fear, which has its own negative consequences. Barron Associates proposes to develop, demonstrate, and commercialize a low-cost system capable of measuring both spatial and temporal gait parameters in freely ambulating subjects, obviating the requirement for access to a gait laboratory or other specialized equipment. Along with fall risk assessment in the elderly, the proposed system will simplify and expand access to accurate gait measurement technology, allowing it to be used in other applications and in subjects' natural environments.